This invention relates to an NC machine tool control method and apparatus for controlling an NC machine tool with a pulse synchronized with a revolution of a main spindle in a machining mode in which a normal machining is performed.
When a new workpiece having a specific configuration is machined by an NC machine tool, the following sequence of procedures is followed. First, a machining program for the NC machine tool machining the workpiece is prepared in accordance with the blueprints of the workpiece. Next, the NC machine tool is actuated for a test machining in order to check whether or not the machining program is correct. When the result of the test machining finds the program is incorrect, the machining program is corrected. Again a test machining is repeated in accordance with the corrected machining program to check whether or not the machining control has been made as intended. The machining program is completed, following such sequence of procedures. Then, in accordance with the completed machining program, the machine tool is automatically operated machine the workpiece.
The test machining is very important among the procedures of the sequence to check whether or not the machining program is correct.
The test machining is conventionally conducted by performing the steps of a machining program having a string of steps, sequentially one by one, or conducted at lower speed than the execution speed of the machining program.
But in such conventional test machining, the incorrect step of the machining program is actually carried out, with results that a cutting tool collides with the workpiece and unnatural forces are exerted on the cutting tool. This is a problem of the conventional test machining.